@article{ref1,
title="American Academy of Pediatrics. Committee on pediatric aspects of physical fitness, recreation, and sports. Competitive athletics for children of elementary school age",
journal="Pediatrics",
year="1981",
author="",
volume="67",
number="6",
pages="927-928",
abstract="<p>[Abstract unavailable]</p> <p>Language: en</p>",
language="en",
issn="0031-4005",
doi="",
url="http://dx.doi.org/"
}